Notes

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Vocabulary

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heat transfer-movement of many from a warmer object to a cooler object
radiation- energy transfer through empty space; sunlight
conduction-heat transfer by direct contact of matter
convection-heat transfer by movement of a heated fluid
density-how much mass in a volume of a substance
convection current-a flow which transfers heat within a fluid

Convection Currents in the Earth's Mantle
Diagram Key:
LS- Lithosphere Cr- Crust AS- Asthenosphere M- Mantle



*Outline*

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• Radiation ----

• Sunlight is the radiation that warms Earth's surface
• The warmth you feel around a flame or open fire are forms of radiation
• Conduction ----

• When a spoon is heated by hot soup, heat is transfered from the soup to the particles that make up the spoon
• Particles near the bottom of the spoon vibrate faster as they are heated so they bump other particles, and heat them too
• Convection ----

• During convection heated particles of fluid begin to flow transferring heat energy from one part of the fluid to another
• Heat transfer by convection is caused by differences of temperature and density within a fluid
• When a liquid or gas is heated the particles move faster, spread apart and takes more space so that the density decreases
• Convection in the Earth's Mantle ----

• Like soup simmering in a pot, Earth's mantle responds to heat sources
• The heat source for these convection currents is from Earth's core and from the mantle itself